+ 1 Votes So after you changed the drive letter OH Smeg Updated - January 30, 2013 at 7:10pm PST How did you dismount the drive? You need to use the Safely Remove Option under all versions of Windows to Dismount the Drive or run the risk of Corrupting the Partition Tables. You can try running Check Disc on the affected drive and it may repair the Partition Tables but depending on how Important the data on it is you may want to pay a Professional to Recover your Data. If it's only just Nice to recover the data run Check Disc without a second thought but if you must recover the Data send it to a professional as the more you unsuccessfully mess with it now the more expensive the recovery is going to be and the less likely you are to recover 100% of the data. Col + 0 Votes Try renaming it back vovokorp Updated - February 6, 2013 at 8:45pm PST how can two drives be in one name ? + 1 Votes What if you just change it back? Slayer_ January 31, 2013 at 12:13pm PST I think Windows likes to reserve the D drive anyways. + 0 Votes You don't mention external disk type Cmd_Line_Dino Updated - February 1, 2013 at 2:54am PST Is it USB or eSATA or something else ? On power up does the drive spin up and do the usual few seconds of activity ? Is the use of conflicting with a CD/DVD/Blueray drive or chip reader or something. On the Win 7 system... Disconnect the problem disk and reboot Run DISKMGMT.MSC. Is some device assigned to ? Be sure to look through the lower pane list. CD, DVD etc appear only there. If there is a then change it to some other letter. Connect the problem drive. Is it visible at all in DISKMGMT.MSC Try a power cycle reboot. + 0 Votes Windows XP Drive letters Merlin the Wiz February 1, 2013 at 4:02am PST Been there done that twice on non-CD laptop computers! Change it Back to F: and it should work. The drive designation appears to be reserved in Windows XP for a CD drive. Even if your computer does not have a CD drive. Merlin + 0 Votes no reserved drive letters, not even in win 2K . . . Who Am I Really February 1, 2013 at 5:07pm PST only reserved drive letters are ones already in use you can't change the drive letter in disk management to one that is already in use on a system with no CD/DVD drive, card reader, or floppy drive that has windows installed on the default C you can assign A:\, B:\, or any letter from \ - Z to any other partition / drive / mass storage device windows assigns the letters sequentially after C thus you generally won't encounter a USB drive getting A or B but if you plug in 23 storage devices you will have used all the letters from \ -> Z:\, and then when you plug in number 24 you will get a drive letter assignment of either A or B in this case however, I agree with Col and I'm leaning more to either the corrupt partition table or a mechanical or electronic/electrical failure of the HDD or USB -> SATA/IDE chip(s) etc. in the enclosure removing it from the USB enclosure and attaching the HDD directly to an internal connector or a known working USB adapter will give some idea about whether or not the electronics are fried in the enclosure or if the HDD has gone for a dump, I've seen these things just go poof for no apparent reason recently had an HDD go poof just by touching the case while it was writing heard a click and then it was gone, (the read / write heads were immediately barbecued) I know it was static because of the dusty & dry environmental conditions in that particular office, but I didn't even feel it leave my finger a static blast up the USB cable while plugging, unplugging or just grabbing it can cook these devices. even a small static blast that you might not even feel can cook toast it a larger static blast can **** a whole trace line right out of a PCB Removing a USB SD card reader, flash drive, or HDD without safe removal can toast the partition table, however, even with safe removal you can still fry it electrically with static discharge There's more than one way for these things to go poof. if it's a partition table corruption there are some tools available that can correct the partition table or attempt to read the data from the disk that appears as unformatted but an electronic / electrical failure will require data recovery services + 0 Votes @ gechurch 4 Cmd_Line_Dino February 4, 2013 at 1:56am PST The point of my advice was to do some first-step basic trouble shooting. Trying the disk on another computer would have been another first step. Evaluate, diagnose, remediate. What would you have advised ? + 0 Votes @OH Smeg Cmd_Line_Dino February 4, 2013 at 9:00am PST About using safely remove ==================== So we should believe you rather than Microsoft ? On there website MS CONTINUES to say it's not needed. I will go with MS considering their decades of experience dealing with a vast universe of hardware. But of course, as MS says, don't pull the cable while there is activity. And why do you and others here keep saying the partition tables will be damaged. First, for the vast majority of systems it's partition table (singular). Second, for those systems it's a single 512 byte sector on the disk which is NEVER changed UNLESS you are reconfiguring the partitions on the disk. Just because it's sector 0 is that why you think it's going to be changed/corrupted ? About power being abruptly removed from an active hard disk =============================================== Disk drives are DESIGNED TO DEAL with the unexpected loss of power. They immediately park the heads in the landing zone. Some use the rotating spindle to generate power to do the last activity and parking. Think about how each day around the world hundreds of thousands of systems either abruptly lose power or are just powered off with no use of system shutdown. And for the vast vast majority nothing happens. And about USB (AGAIN) =================== Here too, USB is designed for plug/unplug with the power on. And here is a tidbit. In XP doing safely remove would drop the USB power. Starting with Vista safely remove no longer drops the USB power. Perhaps an evil MS plot to destroy USB devices ... nah probably not. + 0 Votes Cmd_Line_Dino HAL 9000 Moderator February 5, 2013 at 6:17am PST Feel free to believe what you want to it personally doesn't worry me in the slightest. I will however mention that I make a lot of money by recovering lost data on external HDD that people have corrupted the Partition Table as you seem to prefer I didn't say that it happens with SSD Drives or things with no movable parts but it most defiantly happens with mechanical HDD. I currently have a 2 TB Drive from a customer which is unreadable and they want their data back off it. Easy Money when the customer does stupid things. :^0 Col + 0 Votes More info Windranger February 5, 2013 at 8:40pm PST The HDD is SATA; I can't rename it back because the computer doesn't see it, even in Disk Management. There's no drive assigned with letter D. Of course, any HDD can fail, but this problem coincided with changing the drive letter, so it's quite a low probability that the cause is different. + 0 Votes Windanger Cmd_Line_Dino February 6, 2013 at 2:07am PST Were you able to use the drive for awhile after changing it to ? Have you tried it in another system ? Does it even spin up ?